MAUI-FilePicker选择文件_选择头像

一、代码：

    private async void BtnPickAndShow_Clicked(object sender, EventArgs e)
    {
        try
        {
            var result = await FilePicker.PickAsync(PickOptions.Default);
            if (result != null)
            {
                txt1.Text = $"文件名: {result.FileName}";
                if (result.FileName.EndsWith("jpg", StringComparison.OrdinalIgnoreCase) ||
                    result.FileName.EndsWith("png", StringComparison.OrdinalIgnoreCase))
                {
                    var stream = await result.OpenReadAsync();
                    imgPickAndShow.Source = ImageSource.FromStream(() => stream);
                }
            }
        }
        catch (Exception ex)
        {
            // 用户取消或出现问题
            await DisplayAlert("用户取消或出现问题", ex.Message, "关闭");
        }
    }